Not applicable.
1. Field of the Invention
This invention relates to surface treatment disks, especially to such surface treatment disks which are attachable to rotary tools.
2. Description of Prior Art
Different types of surface treatment disks are available in the market; including abrasive disks, buffing disks, polishing disks, etc. that are attachable to a rotary tool, such as a drill, a saw, a buffing machine, etc., and these machines may be portable or stationary. (Note: The terms xe2x80x9ctreatmentxe2x80x9d, xe2x80x9ctreatingxe2x80x9d, xe2x80x9cfinishingxe2x80x9d and their variations, or equivalents are alternatively used in this application, and indicate the action of a disk applied to a surface.)
In general, the purpose of these disks is to aid in the treatment of surfaces that do not have any high or low relieves or any other intricate shapes. In other words, the surfaces or portions of surfaces to be treated are either flat or if they are not flat, they have a continuous and even shape.
These prior art disks, and the system to treat surfaces therewith were first introduced into the marketplace by the industry in an attempt to maximize the utility and as a result, the demand for power drills, since they would obviate the need to purchase a dedicated sanding machine, which would represent substantial savings to the consumer.
A notable variation of this system consists of a rubber padded disk in conjunction with circular sandpaper adhered or otherwise fastened to said rubber padded disk.
This prior art system fails to provide an adequate alternative to dedicated sanding machines. The reason is precisely that the principles of dedicated sanding machines have been extrapolated to drills and other rotary machines, and thus they have a flat shape. And there is where the problem resides.
Dedicated sanding machines can function with this type of flat disks because their movement is either of an orbital nature or of an oscillatory nature.
When using a dedicated sanding machine, the force is uniformly distributed throughout the surface of the disk and then applied to the surfaces being treated, and the disk may be in a controlled motion when flatly in contact with the surface being treated.
But that is not at all the case with rotary tools, where the movement is of a rotary-centrifugal nature.
When the prior art disks are attached to rotary tools, the results are very far from satisfactory. The method is not practical or functional, as it is demonstrated by the following specific problems:
1) The centrifugal force directs all the action to the periphery of the disk. This constitutes a critical flaw of the system, since the periphery is only a nominal area, while the entire surface area of the disk is virtually inert. Hence, these other problems are derived from this critical defect:
2) If the rotary disk is applied flatly parallel to the surface being treated, a tendency to inertia occurs. (See FIGS. 1 and 3.) A xe2x80x9cbrakexe2x80x9d effect is produced and any abrasive or polishing or otherwise finishing effect is voided.
3) If the rotary disk is applied in an angle to the surface, all the finishing effect will be applied by the periphery of the disk, treating a minimal area, as indicated before. (See FIGS. 2 and 3.) But this is further aggravated by the concentrated strong effect, particularly if the disk has abrasive properties, that will have a carving effect on the surfaces being treated, which is additionally very difficult to control.
4) Due to the high resistance offered by the surface being treated to the disk, a vibration is provoked. This vibration causes the disk to detach from the rotary tool very frequently.
5) Likewise, when using sand paper attached to a padded disk, this vibration causes the sand paper to be constantly detached. This has an even more damaging effect if the sand paper is adhered to the padded disk. After two or three detachments and re-attachments, the fastening strength of the adhesive is substantially reduced. This is further aggravated by all the dust that contaminates the adhesive coating of the sand paper, rendering it useless, As a result of the preceding, other significant problems are generated:
6) Excessive fatigue and low productivity are imposed on the operator.
7) Surfaces are unevenly treated.
8) Uneven wear of finishing disks and accessory materials occurs.
9) High risk of slipping of the rotary tool, due to the uneven contact of the surfaces, which entails a risk of harm to operator, his/her clothes, and/or surrounding objects.
The preceding problems relate to the use of the disks when flatly applied to the surface being treated, or when applied in an angle. But there is another scenario. Probably the most common scenario, with some of the preceding disadvantages, plus some others, as follows:
10) In an effort to equilibrate the two extreme modes of operation mentioned before (a. Applying the disk flatly against the surface being treated, and b. Applying the disk in an angle to the surface being treated,) the operator may instinctively force the disk into a more natural shape for the task, if the disk offers some flexibility. While the effort is substantial (most probably operator will use both hands) the flexibility is minimal. (See FIG. 4.) Thus, what is achieved is an increased fatigue to operator in exchange for an insignificant improvement in performance, plus a highly enhanced risk of disengagement of the disk from the rotary tool, and/or sand paper or any other surface treatment accessory from the disk. This effort to force the disk into a more co-operative shape, may cause the fracture of the disk, as it commonly happens with wire disks for abrasive purposes, as described by FIGS. 5, 6 and 7.
Accordingly, several objects and advantages of my invention are:
1. Permits an easier treatment of surfaces, and consequently reduces fatigue.
2. Permits a faster treatment of surfaces, and consequently increases productivity.
3. Permits more control of the treatment of surfaces.
4. As a result of #3., permits a uniform and even treatment of surfaces for a better quality job.
5. Prevents the uneven wear of the finishing materials.
6. Prevents the rupture of abrasive metallic disks, that occurs in the concentric surrounding area where connected to the tool.
7. Prevents the slipping of the disks due to an uneven contact with surfaces being treated.
8. As a result of #7., prevents any accident against operator of rotary tool, operators clothes and/or any surrounding objects.
9. Minimizes incidence of disengagement from the tool, which requires a constant re-attachment of the disk to the machine or tool as vibration is reduced or eliminated.
10. When using sand paper disks, permits a stronger adhesion, as vibration is reduced or eliminated, preventing the need to constantly re-attach the sand paper disks
11. As a result of #10., extends durability of paper disks, as repeated attachments wear their adhesive strength.
12. The good bonding quality of the paper disks and the usefulness of the disks is also extended as contamination of the adhesive substance that occurs when the disks are detached and exposed to the dust is prevented.
13. Manufacturing of the disk appears highly compatible with the established systems. Implementation should be facilitated by this.
14. As a result of #13., costs to produce should be very similar. Price to consumer could be very similar, while there is a significantly higher value.
15. As this system actually uses and exploits the centrifugal force to treat surfaces, disks could be of a larger diameter for a yet better performance.
Further objects and advantages of my invention will become apparent from a consideration of the drawings and ensuing description.
In accordance with the present invention an improved surface treatment disk for rotary tools comprises a conical shape, said conical shape having an obtuse angle.